There was a big fire at a hospital which inflicted serious damage. Touya's mother, Suzuno, fell victim to its flames. After ten years he still can't overcome his sadness. But he somehow enjoys his life with Makina, his younger sister, and Saya. One day he sees a girl who looks quite like Suzuno. He can't forget her, and goes after her. He finally talks to her and thinks she is definitely Suzuno. All of a sudden, she attacks him with smile, and he almost loses his life. But a girl with a sword appears in front of them and saves him. He doesn't know what's going on, but he thinks, "Is she still alive?" He starts to search for the truth...